Home / 258.00-387.35-219.72

Finding the Fourth Proportional to 258.00, 387.35 and 219.72

Calculator

Solution

The fourth proportional to 258.00, 387.35 and 219.72 is: 329.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    258.00 : 387.35 = 219.72 : x
  2. Step 2: Convert to fraction form
    258.00/387.35 = 219.72/x
  3. Step 3: Cross multiply
    258.00x = 387.35 × 219.72
  4. Step 4: Simplify right side
    258.00x = 85,109.72
  5. Step 5: Solve for x
    x = 85,109.72/258.00
  6. Step 6: Final answer
    x = 329.89

Related Problems

Find fourth proportional to 129.00, 193.67 and 109.86
Half scale
Find fourth proportional to 515.99, 774.70 and 439.45
Double scale
Find fourth proportional to 259, 388.85 and 220.72
Similar ratio
Find fourth proportional to 386.99, 581.02 and 329.59
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.